The spotlight on solar energy has been ON since the late 2000s, but it has become prominent only in the recent years due to rising concerns about global warming and the effects of climate change caused by energy production across the globe. The need for sustainable energy and increased costs for producing energy have given rise to the residential solar power market.
Although the use of solar energy to power lights, lanterns and torches goes way back to the late 90’s, today solar energy is seen as an opportunity less explored in the past. Scientists and solar engineers are relooking into these unutilized synergies and possibilities of solar energy while bringing innovation into modern day homes.
Interesting Fact to Digest: Several companies have already powered cars to run on solar energy which is a testament to the future of energy.
Interesting Read to Crunch: Here is why solar energy will change the way we power homes in the future
According to an analysis by Mordor Intelligence, the residential solar industry is expected to register CAGR of more than 10.5% during the forecast period of 2022-2027 and the largest market for it will be Asia Pacific.
In India, the 20GW target set for the total solar energy capacity in 2022 was achieved four years in advance surpassing all expectations of the Energy Ministry. The total energy capacity as of March 2022 is 53.997 GW. The clear indication is that the way forward is very much evident and clear.
With advancements and technological perfections, it is only a matter of time before which we can see solar energy for residential applications being adopted across all regions especially in remote places where electricity supply has been a hurdle.
The renewable energy source has drawn significant interest from homeowners. Most often, not having clear answers regarding the processes involved in solar panel installation becomes a detriment for these homeowners. As a relatively new trend and technology, the awareness about solar energy and its usage is a challenge.
In this Solar Energy 101 post, we will discuss the solar panels, types of solar panels available, how solar panels work and how many solar panels are needed to power a house.
What are solar panels?
Solar panels also called photovoltaic, or PV panels are a series of solar cells combined into one unit. These are used to convert light from the sun, which is composed of energy particles called "photons", into electricity that can be used to power electrical loads.
Solar panels are used for different applications ranging from powering water heaters and charging batteries to fueling satellites.
The power produced by the solar panels are directly proportional to the sunlight they are exposed to. So, with exposure to the right amount of sunlight, the solar panels can produce power that can be used directly or stored to be used when needed.
Types of solar panels available in the market
- Monocrystalline Panels - These are made from a single pure silicon crystal that is cut into several wafers. They are the most space-efficient and longest-lasting type of panels and are also the most expensive.
- Polycrystalline Panels - These are made from different silicon crystals. Here the silicon fragments are melted and poured into a square mold. This type of panels is less efficient and are affordable in comparison to others.
- PERC Panels - These are an improved and optimised version of the traditional monocrystalline cells where there is a passivation layer in the rear surface of the cell that enhances efficiency further. While these panels are expensive due to being a new technology, they in turn offer very good efficiency and effectiveness.
- Thin-film Panels - These panels are made of fine layers that are thin and flexible. Each panel does not require a frame backing, making them lighter and easier to install. They are less efficient in comparison to conventional panels and are also expensive.
The above types of panels are used based on the application. They are also used in conjunction with each other where there is a requirement for a hybrid system. Typically, in residential applications, Monocrystalline and Polycrystalline panels are used.
How solar panels work?
- Solar panels absorb sunlight
- They convert the light into DC power
- Using an inverter (String, Micro or Hybrid) they convert DC to AC power
- The AC power is used in homes for different applications
- Excess power is sent to the grid or stored in the battery for future use
How many solar panels are needed to power a house?
The exact number of solar panels needed for any home will depend on factors like where you live, how much energy you typically use, and how much power your panels can generate, etc. While it seems too generic and common, the answer to this question is simple.
The number of solar panels to be used is directly proportional to amount of power to be generated. Which means, if you consume an average of 25 KWh electricity every day in your home, you’ll need to use the number of solar panels that can meet the demand.
Let’s look at the three main components that help in determining the number of solar panels that must be installed in a home:
- Average energy usage
To calculate the number of panels needed, one has to first understand how much electricity is metered on a daily, monthly and yearly basis. This can easily be done by looking at the electricity bills to understand the average usage over the last month and before that. Take an average of the usage over the previous 12 months and if there is increase in the usage due to any application or appliance, keep it in consideration.
On an average, a household in India uses 29.5 KWh electricity daily. That sums up to 885 KWh a month and 10,620 KWh every year.
- Solar Panel Output
Based on the type of solar panel that will be used, one can understand the expected output keeping in mind the factors that affect it like the climate conditions at the installation place, sunlight, shade, etc. This is called the power rating and it is measured in Watts. Solar panels usually come with a power rating that can be a quantification for calculating the number of panels needed.
For example, if you buy a solar panel with an output of 325 Watts, you can directly multiply it with the number of hours of sunlight it gets in a day to calculate the total estimated output. This in turn helps in determining the weekly, monthly, and yearly output. With one panel if we can meet 1/10th of the demand, then we will need to use 10 panels to meet the full demand.
- Physical Location
Physical location affects the efficiency of home solar panels. As understood by all, solar panels are the most effective and fruitful where there is sunlight for most part of the day continuously around the year. So, places like Jaipur, Hyderabad, Bangalore, Chennai, Mumbai, Delhi, etc. can reap the most by using the solar panels in comparison to places like Shimla, Shillong, Darjeeling, J&K, etc.
Based on the location and seasons, we can calculate the number of hours in a day that sunlight can be seen. The number of hours multiplied by the power generated by one panel will give a fair idea as to how many of the same panels will have to be used to meet the demand.
The feasibility of using solar panels depends on place to place and their efficiency relies on many environmental conditions. So, understanding this beforehand is very important for any homeowner to avoid losses due to poor analysis.
If you want to quickly estimate the number of solar panels you would require, we have created an accurate and convenient tool for you. Just input your electricity bill and this tool will calculate the number of solar panels you would require. Here’s the calculator – Solar Calculator
Solar panels are an essential component of any residential solar energy setup. While there are many applications of solar energy systems, the type of panels used will be based on the requirements and essentials.
It is important for homeowners to understand the factors influencing the solar power output so that they can make the right call on feasibility of usage, the quantification of solar panels that are to be employed and get a fair idea as to return on investment. The three main components to consider for determining the number of panels include average energy usage, solar panel output and physical location.
With the right implementation and quantification, solar panels are very rewarding in the long run. They not only utilize the free source of energy to power our homes but will also help in contributing towards a better future.
Speak with our expert to understand the feasibility for your setup or if you wish to get a free analysis on how many panels are needed for your home